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10 questions
My books aren’t on the table where I always leave them. They _____ been taken by my husband.”
had
had not
may have
must
“Dinosaurs didn’t necessarily die off gradually from climate change; they _____ been killed off quickly by some sudden event. I guess”
a. could have
b. couldn’t have
c. had
could have
had
couldn't have
should
I don’t believe in any of the other theories. There is no doubt: Giza _____ been built by the ancient Egyptians
could
might not have
might have
had to have
Some of the visitors brought only long pants and sweaters; they _____ been told that it’s so hot and humid here
must have
could have
must not have
should
His story is really _____. I doubt that those things could have really happened.
unsolvable
questionable
probable
provable
I think she's telling the truth. Her description of the events very ____ to me.
questionable
believable
solvable
unprobable
The question of whether or not solar power is the answer to the energy crisis is _____. Experts offer many other solutions as well.
debatable
believable
provable
unsolvable
There are several theories about the mystery of the MH370, but with so little evidence, none are _____
believable
debatable
provable
believable
Peter thinks the John was lying about the value of that suitcase, but I actually think what he said is _____.
solvable
questionable
believable
debatable
The mystery of what happened to the famous US pilot Amelia is most likely ____ since her body and the plane have never been found.
believable
provable
debatable
unsolvable
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